encho: Tape Calculator

Fix any line and everything below recomputes. Save your tape as a named sheet, total always in view. No ads, one-time ¥800, all math stays on device. Try it free.

The tape calculator you can edit — fix any line and everything below recomputes. Save your tape as a named sheet, with the total always in view. Every internal calculation runs in full-precision Decimal.

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On a normal calculator, one wrong key means starting over. Dencho keeps every calculation on a tape you can edit: tap any line — the starting value, an operator, or an operand — and every line below recomputes. Changed lines briefly highlight. Inserting, reordering, and deleting lines recompute the same way, and a one-tap Undo rolls the whole last action back at once.

Name a tape and it's saved as a sheet. The list is sorted by last edited and shows each sheet's total. A running total bar always shows the sum and line count, so you never re-add just to ask "where am I now?"

Rounding mode (half-up, up, or down), decimal places (0–4), and the tax rate are saved per sheet — reopen an old sheet and its results reproduce exactly, with that sheet's own settings.

Percentages follow business-calculator conventions: 1000 + 8% = 1080, 1000 − 8% = 920, 1000 × 8% = 80. Add-tax and remove-tax split values to the yen. Because each line is rounded to a real amount, a division like 1000 ÷ 3 = 333, then × 3 = 999 — the ledger-correct behavior.

WHAT YOU GET • Every calculation stays on the tape; tap any line to edit and everything below recomputes • Save named sheets, sorted by last edited, each with its total; duplicate and search • Note-only lines you can insert — they don't affect the math but are included in sharing and search • Rounding mode × decimal places × tax rate, saved per sheet • Three text sizes, light/dark, and one-action-per-transaction Undo/Redo

BUILT DIFFERENTLY, ON PURPOSE • No ads, no tracking. All math stays on your device and the app makes no network calls (except Apple's StoreKit for purchases) • The whole tape calculator (editing, recompute, notes, rounding, tax, totals, Undo) is free; you can save up to 2 sheets • The one-time Dencho Pro (¥800) makes sheets unlimited and adds widgets and sheet sharing (text export). There is no subscription • If Pro ever lapses, all your saved sheets remain readable — only editing and creating beyond the third sheet pauses — and repurchasing restores everything instantly

Dencho Pro is a one-time ¥800 purchase. Restore Purchases is available anytime in Settings. Terms of Use and Privacy Policy are linked in-app and at the links below.

Dencho is a calculation-notes tool. It does not guarantee compliance with statutory bookkeeping or Japan's Electronic Books Preservation Act. "Ledger" is used as an analogy for how the tape is kept. Always verify results yourself.